Question

我有这个问题：

Select b.building_pk, bil.building_fk, bil.BillingAccountStatus_fk, b.ACTL_TNT_CT 
From [DB].[Schema].Building b (nolock)
left Join [DB].[Schema].Billing bil (nolock) on bil.building_fk = b.building_pk
join ##GlobalTempTable1 tt (nolock) on tt.Building_fk = b.building_pk
Order by b.building_pk;

工作正常。但是我希望覆盖NULL列和bil.building_fk列中结果集中的bil.BillingAccountStatus_fk，因为并非Billing tbl中的所有内容都存在于构建表中。

所以在下面写了下面的查询，但收到此错误消息。

Msg 102，Level 15，State 1，Line 7语法不正确＆＃39; =＆＃39;。

请协助。

SELECT b.building_pk, bil.building_fk As [BLD Key from Billing], bil.BillingAccountStatus_fk, b.ACTL_TNT_CT As [ActualTenantCount] 
FROM [DB].[Schema].Building b (nolock)
join ##GlobalTempTable1 tt (nolock) ON tt.Building_fk = b.building_pk
left Join [DB].[Schema].Billing bil (nolock) ON
CASE
    WHEN bil.building_fk IS NOT NULL 
        THEN bil.building_fk = b.building_pk AND bil.BillingAccountStatus_fk = bil.BillingAccountStatus_fk
    WHEN bil.building_fk IS NULL
        THEN bil.building_fk = NULL AND bil.BillingAccountStatus_fk = 'Not in Billing'
    END
ORDER BY b.building_pk;

Answer 1

很难说你想要做什么，因为这是非常错误的。不过，我认为您希望保持FROM相同，并将CASE语句放到SELECT中。

Select b.building_pk, CASE WHEN bil.Building_fk IS NULL THEN 'Not in Billing' ELSE bil.building_fk END as building_fk, bil.BillingAccountStatus_fk, b.ACTL_TNT_CT 
From [DB].[Schema].Building b (nolock)
left Join [DB].[Schema].Billing bil (nolock) on bil.building_fk = b.building_pk
join ##GlobalTempTable1 tt (nolock) on tt.Building_fk = b.building_pk
Order by b.building_pk;

或者，更好的是，在这里使用COALESCE()：

Select b.building_pk, COALESCE(bil.Building_fk,'Not in Billing') as building_fk, bil.BillingAccountStatus_fk, b.ACTL_TNT_CT 
From [DB].[Schema].Building b (nolock)
left Join [DB].[Schema].Billing bil (nolock) on bil.building_fk = b.building_pk
join ##GlobalTempTable1 tt (nolock) on tt.Building_fk = b.building_pk
Order by b.building_pk;

Answer 2

CASE表达式不能用于设置您用于JOIN的标准，它们可以在JOIN条件的比较运算符的任意一侧使用，但是我认为您不需要，我认为您需要LEFT JOIN中的COALESCE()和SELECT：

SELECT b.building_pk
     , bil.building_fk As [BLD Key from Billing]
     , COALESCE(bil.BillingAccountStatus_fk,'Not in Billing')
     , b.ACTL_TNT_CT As [ActualTenantCount] 
FROM [DB].[Schema].Building b 
join ##GlobalTempTable1 tt 
   ON tt.Building_fk = b.building_pk
left Join [DB].[Schema].Billing bil 
   ON bil.building_fk = b.building_pk
ORDER BY b.building_pk;

修改：注意BillingAccountStatus_fk来自bil双方，因此已从JOIN条件中删除。

Answer 3

我猜你正试图做这样的事情：

SELECT b.building_pk, bil.building_fk As [BLD Key from Billing], bil.BillingAccountStatus_fk, b.ACTL_TNT_CT As [ActualTenantCount] 
FROM [DB].[Schema].Building b (nolock)
join ##GlobalTempTable1 tt (nolock) ON tt.Building_fk = b.building_pk
left Join [DB].[Schema].Billing bil (nolock) ON
    (bil.building_fk IS NOT NULL AND 
        (bil.building_fk = b.building_pk AND bil.BillingAccountStatus_fk = bil.BillingAccountStatus_fk))
    OR (bil.building_fk IS NULL AND
        (bil.building_fk = NULL AND bil.BillingAccountStatus_fk = 'Not in Billing'))
ORDER BY b.building_pk;

我将被误导使用nolock再过一天......

JOIN中的案例陈述

3 个答案: